A drone photo shows the construction site of the Sanya River estuary passage project in Sanya, south China's Hainan Province, Oct. 12, 2024. The Sanya River estuary passage project undertaken by China Railway 20th Bureau Group is making steady progress. As the first underwater tunnel in Sanya, the project will further optimize the urban spatial layout and facilitate the development of the Hainan Free Trade Port. (Xinhua/Yang Guanyu)
Workers work at the construction site of the Sanya River estuary passage project in Sanya, south China's Hainan Province, Oct. 12, 2024. The Sanya River estuary passage project undertaken by China Railway 20th Bureau Group is making steady progress. As the first underwater tunnel in Sanya, the project will further optimize the urban spatial layout and facilitate the development of the Hainan Free Trade Port. (Xinhua/Yang Guanyu)
Workers work at the construction site of the Sanya River estuary passage project in Sanya, south China's Hainan Province, Oct. 12, 2024. The Sanya River estuary passage project undertaken by China Railway 20th Bureau Group is making steady progress. As the first underwater tunnel in Sanya, the project will further optimize the urban spatial layout and facilitate the development of the Hainan Free Trade Port. (Xinhua/Yang Guanyu)
Workers work at the construction site of the Sanya River estuary passage project in Sanya, south China's Hainan Province, Oct. 12, 2024. The Sanya River estuary passage project undertaken by China Railway 20th Bureau Group is making steady progress. As the first underwater tunnel in Sanya, the project will further optimize the urban spatial layout and facilitate the development of the Hainan Free Trade Port. (Xinhua/Yang Guanyu)
A drone photo shows the construction site of the Sanya River estuary passage project in Sanya, south China's Hainan Province, Oct. 12, 2024. The Sanya River estuary passage project undertaken by China Railway 20th Bureau Group is making steady progress. As the first underwater tunnel in Sanya, the project will further optimize the urban spatial layout and facilitate the development of the Hainan Free Trade Port. (Xinhua/Yang Guanyu)
Workers work at the construction site of the Sanya River estuary passage project in Sanya, south China's Hainan Province, Oct. 12, 2024. The Sanya River estuary passage project undertaken by China Railway 20th Bureau Group is making steady progress. As the first underwater tunnel in Sanya, the project will further optimize the urban spatial layout and facilitate the development of the Hainan Free Trade Port. (Xinhua/Yang Guanyu)
A drone photo shows the construction site of the Sanya River estuary passage project in Sanya, south China's Hainan Province, Oct. 12, 2024. The Sanya River estuary passage project undertaken by China Railway 20th Bureau Group is making steady progress. As the first underwater tunnel in Sanya, the project will further optimize the urban spatial layout and facilitate the development of the Hainan Free Trade Port. (Xinhua/Yang Guanyu)
An aerial drone photo shows the construction site of the Sanya River estuary passage project in Sanya, south China's Hainan Province, Oct. 12, 2024. The Sanya River estuary passage project undertaken by China Railway 20th Bureau Group is making steady progress. As the first underwater tunnel in Sanya, the project will further optimize the urban spatial layout and facilitate the development of the Hainan Free Trade Port. (Xinhua/Yang Guanyu)
Workers work at the construction site of the Sanya River estuary passage project in Sanya, south China's Hainan Province, Oct. 12, 2024. The Sanya River estuary passage project undertaken by China Railway 20th Bureau Group is making steady progress. As the first underwater tunnel in Sanya, the project will further optimize the urban spatial layout and facilitate the development of the Hainan Free Trade Port. (Xinhua/Yang Guanyu)
An aerial drone photo shows the construction site of the Sanya River estuary passage project in Sanya, south China's Hainan Province, Oct. 12, 2024. The Sanya River estuary passage project undertaken by China Railway 20th Bureau Group is making steady progress. As the first underwater tunnel in Sanya, the project will further optimize the urban spatial layout and facilitate the development of the Hainan Free Trade Port. (Xinhua/Yang Guanyu)
